The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 13, 1992
Filed:
Feb. 26, 1991
Applicant:
Inventors:
Ram L Bedi, San Jose, CA (US);
Alan R Selfridge, Palo Alto, CA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
367152 ; 367157 ; 310337 ; 310322 ;
Abstract
A hydrophone for calibrating lithotripters includes a spot poled disc of piezoelectric material which is mounted on a brass cylinder backing. A coaxial cable is electrically connected to one surface of the disc through the brass backing and the opposing surface of the disc. A mixture of polymeric material and microballoons is provided to protect the interconnection of the center conductor and the opposing surface of the disc and prevent damage due to the incident ultrasonic shock waves. The brass backing is placed in a suitable housing of phenolic material. A process in fabricating the piezoelectric disc and assembling the hydrophone is disclosed.